Pressing tool,specifically hand press



Nov. 4, 1969 F. G. LAUX PRESSURE TOOL, SPECIFICALLY HAND PRESS 2Sheets-Sheet F'iled March 22. 1965 INVENTOR M M M R m w W EEE 5: E:

FIG. 4

United States Patent 3,475,946 PRESSING TOOL, SPECIFICALLY HAND PRESSFriedrich Giinther Laux, 301 Konigsweg, 1 Berlin 39, Germany Filed Mar.22, 1965, Ser. No. 444,098 Claims priority, appliclation Ggrmany, June12, 1964,

Int. (:1. B21d 9/08 US. Cl. 72-409 7 Claims ABSTRACT OF THE DISCLOSUREThis invention relates, in general, to tools for compressing articlessuch as electrical connectors, and more particularly relates to suchtools having advantageous force-multiplying and actuating features.

One feature of this invention pertains to the provision, in acompression tool, of a rotary eccentric linkage which is driven by afluid pressure-actuated rack moved along a substantially linear path.

Another feature of this invention pertains to the provision, in a toolsuch as is described above, of a fluid pressure piston assembly which ispivotally coupled relative to an eccentric linkage so as to serve as amanual actuating handle for the linkage.

An advantage of the features described above is a resultant mechanicaladvantage which is significantly higher than that generally obtained byprior art tools of related types.

These and other and further features, advantages, and new results ofthis invention will be more clearly illustrated, specifically pointedout, and fully claimed in the following specification and claims, and inthe appended drawings, in which:

FIG. 1 is a side elevation view of a compression tool constructed inaccordance with this invention;

FIG. 2 is a partially sectioned side elevation View of the tool of FIG.1;

FIG. 3 is a section view taken along the line XIXI of FIG. 2; and

FIG. 4 is a partial section view taken along the line XIIXII of FIG. 2.

Referring now more particularly to the drawings, it may be seen that theillustrated tool comprises, generally, a body formed by a pair of sideplates 91, a pair of handles 102, 103 coupled to the body, and a pair ofopposed die members 5, 6 mounted between the plates 91.

A pair of parallel grooves 3, 4 are formed in the side pieces 91, toreceive die members 5 and 6 in sliding relationship. At one end ofgrooves 3, 4, die member 6 abuts against a movable thrust-bolt 18, andat the other end of the grooves, a stop-bolt 9 is provided to engage diemember 5 so as to capture the dies within the tool. The stop bolt 9 isformed with a knob 12 at one end to facilitate insertion and withdrawalof the bolt in bores 10, 11 in order to permit changing of the diemembers. An annular groove 13 or equivalent detent means may be providedon the bolt 9 to coact with side plates 91 or bores 10, 11, forretention purposes. And, a torsion spring element 50 is coupled to diemembers 5, 6 at its opposite ends 58, 59, to act as a spacer for biasingthe Patented Nov. 4, 1969 die members into spaced-apart relationshipwithin the tool. In use, the biasing eifect of spring element 50 isovercome by force transmitted to die member 6 from movable thrust-bolt18; movable die member 6 is thus advanced toward fixed die member 5 soas to compress an article between the opposed working faces 54, 55 ofthe die members.

The movable thrust-bolt 18 which advances die member 6 toward die member5, is controlled by a drive assembly comprising: pressure transfermembers 20, eccentric pivot journals 21, toothed pinion wheel 71,toothed rack member 72, and handle 103 which includes piston andcylinder 76. In brief, the operation of this assembly relies upon thetoothed rack 72 to convert linear motion into rotary motion of pinionwheel 71 about the pinion journal 23; the rotary motion of pinion wheel71 is then translated into linear motion of thrust bolt 18 by means ofpressure transfer members 20, which are coupled to eccentric pivotjournals 21. The pivot journals 21 are directly coupled to pinion wheel71 for rotation about pinion journal 23, but are eccentric with respectto the central axis of journal 71 so as to achieve the desired lineardisplacement of thrust-bolt 18 at wheel 71 rotates. The thrust-bolt 18is provided with shaped end portions 19 which fit within guide grooves3, 4, so as to assure linear displacement of the bolt in line with diemember 6. This power transmission train provides a high mechanicaladvantage which results in die member 6 being urged toward die member 5with a substantially higher force than might be obtained through directforce take-01f from a manual or fluid pressure input force alone.

For various reasons, operation of this tool often will require rackmember 72 to advance, withdraw, and advance again, while rotating pinionwheel 71 in one direction only. In order to permit this mode ofoperation to occur, toothed rack 72 is pivotally coupled to the end ofpiston 75 so that it may swing into or out of engagement with the teethof pinion wheel 71, and a holding pawl 132 is provided on the body ofthe tool for preventing rotation of wheel 71 in a clockwise direction(as seen in FIG. 2). Pawl 132 is pivotally mounted to side plates 91 bymeans of a peg 133, and is provided with a compression spring 134 tobias the tip of the pawl into engagement with the teeth on pinion wheel71. The pawl is further provided with a knurled extension lever 135,which may be manually depressed to disengage the pawl from the pinionWheel 71 for rapid positioning of dies 5, 6. Such rapid positioning maybe accomplished, conveniently, through use of key bar 70 which iscoupled to the end of pinion journal 23 for manual rotation of pinionwheel 71. Toothed rack 72 pivots about peg 73 on a fork extension 74 atthe end of piston 75, and a tension spring 128, anchored at its oppositeends to a projection 127 on rack 71, and to fork 74, serves to bias rack72 into engagement with pinion wheel 71 in the direction shown by arrow129.

The handles 102, 103 which are coupled to the body of this tool,comprise a substantially fixed handle 102, and a movable handle 103,respectively. The fixed handle 102, which is employed for supporting andpositioning the tool, comprises a base 98 which is secured to the sideplates 91 by means of pegs 99. A threaded bore 100 within base 98,receives a mating threaded extension 101 on the handle 102, tofacilitate removal and reattachment.

Movable handle 103 serves a dual function: in one capacity it is ahousing for cylinder 76 and piston 75 which actuate the tool in responseto fluid pressure supplied from a fluid pressure source (not shown); ina second capacity, the handle may be manually pivoted relative to thebody of the tool so as to produce rotation of pinion wheel 71independently of fluid pressure in cylinder 76. Handle 103 comprises: atubular base 87 which is pivotally coupled to side plates 91 by means ofprojecting journals 88; cylinder body 76; and tubular connector 111which provides means for introducing pressurized fluid into cylinder 76.As shown most clearly in FIG. 3, projecting journals 88, covered by caps89, are fitted within mounting holes 90 in side plates 91, so that thecaps 89 serve as anti-friction bearings between the journals 88 and theholes 90.

When the tool is to be used with fluid pressure actuation only, handle103 is locked against rotation about journals 88 by means of locking peg93. FIGURES 3 and 4 illustrate operation of this locking peg mostclearly. As shown in FIG. 3, the peg extends through bores in sideplates 91, and is provided at one end with a retention ring 94, and atthe other end with a knob 92 which enables an operator to rotate thepeg, manually, about its own axis. A retention plunger 95, locatedwithin a bore in knob 92, is biased against a dimple 97 in side plate 91by means of a compression spring 96, in order to retain the peg 93 in adesired rotary position. The outer cylindrical surface of peg 93cooperates with a mating groove 125 formed in tubular base 87 of handle103 to prevent pivotting of the base 87 about journals 88. Along thelength of peg 93, a portion of the cylindrical surface is cut away toform a recess 124. When it is desired to free handle 103 for pivotalmotion about journals 88, the peg 93 is rotated by means of knob 92until recess 124 is located in substantially opposed relation to groove125. The surface of peg 93 is then fully disengaged from groove 125 andtubular base 87 may be pivoted freely on journals 88.

When handle 103 has been freed for pivotal motion about journals 88,manual operation of this compression tool may be achieved by alternatelyswinging handle 103 toward and away from handle 102. FIG. 2 illustratesclearly that the central axes of pivot peg 73 for rack 74, and of pivotjournals 88 for handle 103, are offset from one another by an amount, e,as shown in FIG. 4. As a result of this offset, or eccentricity, pivotalmotion of handle 103 causes toothed rack 72 to advance along asubstantially linear path relative to pinion wheel 71, thereby producingrotation of the pinion wheel. For example, as shown in FIG. 2,counter-clockwise rotation of handle 103 toward handle 102 from theposition shown, will displace rack member 72 toward the right, and willcause counter clockwise rotation of pinion wheel 71. As handle 103 isreturned in a clockwise direction, to the position shown in FIG. 3,holding-pawl 132 will prevent pinion wheel 71 from rotating in aclockwise direction, and bias spring 128, acting on rack member 74, willpermit the teeth on the rack to disengage successively from the teeth onthe pinion wheel to achieve sliding relative motion between the rack andwheel.

To achieve fluid pressure operation of this compression tool, handle 103is locked in the position shown in FIG. 2 by means of locking peg 93,and fluid under pressure is introduced into hose 105. The hose issecured to a sleeve 108 by a screw collar 104 which has internal threads113 which engage external threads on sleeve 108. This sleeve is coupled,in turn, by threads 110, 119 to cylinder 76. Screw collar 104 isactually coupled to the end of a further connector member 106 which isconnected, in turn, to the end of hose 105. An O-ring seal 109 ispositioned between the members 106 and 108.

The member 106 carries a spring ring 123 to retain the screw collar 104on the end of the member 106. The end of the member 106 is formed withan annular rim 122 to prevent the screw collar 104 from being pulled offthe end of member 106.

The members 106 and 108 incorporate ball valves, which are adapted toopen when the two members 106 and 108 are connected so as to allowpressurized fluid to be applied to the piston 75, and which are adaptedfurther to close when the two members 106 and 108 are 4 disconnected,thus preventing leakage of fluid from either the hose or the cylinder76.

The member 106 has a tubular extension 107 which houses a ball valve114. The ball 114 can either abut a seat 116 to prevent liquid frompassing out of the member 106 or abut a seat 112 to allow the liquid topass out of the member 106. The ball 114 is urged towards the seat 116by a spring 115.

Similarly, the member 108 houses a ball 117 which can either abut a seat121 or a seat 118, and is urged towards the seat 121 by a spring 120.

Connection of the two members 106 and 108 causes the balls 114 and 117to be displaced by each other from their seats 116 and 121 respectively,against the action of the springs and respectively, so as to allowpressurized hydraulic liquid to be applied to the piston 75. When thetwo members 106 and 108 are disconnected, the balls 114 and 117 areurged back against the seats 116 and 121, respectively, by the springs115 and 120, respectively, to prevent any loss of hydraulic liquid fromthe hose 105 or cylinder 76. Hydraulic operation of this tool thus maybe accomplished by successfully reciprocating piston 75 within cylinder76 until rack 72 has produced the desired rotation of pinion wheel 71.

To achieve the desired mode of operation for piston 75, a compressioncoil spring 79 is mounted on a stem 78 secured to the cylinder 76. Thestem 78 has a head 80 at its free end against which one end of thespring 79 abuts, the other end of the spring abutting against aretaining ring 81 carried by the piston 75. The spring 79 thus urges thepiston 75 to the left, as viewed in FIG. 2. The is an O-ring seal 77between the piston 75 and the cylinretaining ring 81 is held in positionby a spring ring 82. There is an O-ring seal 77 between the piston 75and the cylinder 76.

A tubular connector member 111, including a sleeve 83, is threaded ontothe free end of cylinder 76. A seal 84 is positioned between the sleeve83 and the cylinder, and a limit ring 85 is carried by the piston 75against a shoulder 86 in the piston. As the piston 75 moves toward theright, the limit ring 85 travels along a recess 131 in the cylinder 76until it abuts against a shoulder formed at one end of the recess 131.The travel of the piston 75 is thus limited.

It has previously been mentioned in this specification that pinion wheel71 may be rotated conveniently, without use of handle 103 or fluidpressure, by means of a key handle 70 coupled to pinion journal 23.However, as a result of the interaction of pawl 132 and rack 72 with theteeth on pinion wheel 71, a manual rotation of the pinion wheel by meansof key handle 70 will normally be limited to a counter-clockwisedirection (as seen in FIG. 2), only. It is a further feature of thisinvention that release means are provided to permit pinion wheel 71 tobe rotated freely about its axis in either direction: Holding pawl 132may be disengaged conveniently, as previously described, by manuallydepressing extension lever portion 135 to overcome the biasing action ofspring 134. Rack 72 may be disengaged, also, from the pinion wheel 71 bymoving handle 103 beyond the position shown in FIG. 2 in a clockwisedirection as indicated by arrow 126. Free rotation of pinion wheel 71 isof particular advantage for rapidly positioning the die merlnbers 5, 6to engage or release an article within the too The invention has thusbeen described, but it is desired to be understood that it is notconfined to the particular rms or usages shown and defined, the samebeing merely illustrative, and that the invention may be carried out inother ways without departing from the spirit of the invention;therefore, the right is broadly claimed to employ all equivalentinstrumentalities coming within the scope of the appendant claims, andby means of which objects of this invention are attained and new resultsaccomplished, as it is obvious that the particular embodiments hereinshown and described are only some of the many that can be employed toobtain these objects and accomplish these results.

What is claimed is:

1. A compression tool capable of producing a mechanical advantage on theorder of 1:600, for compressing articles between a pair of dies,comprising:

a body;

a toothed pinion wheel rotatably mounted to said body;

a fixed die coupled to said body;

a movable die coupled to said body;

an eccentric linkage coupling said toothed pinion wheel to said movabledie for moving said movable die relative to said fixed die upon rotationof said pinion wheel;

a toothed rack member having teeth operatively engaging said pinionwheel for rotating said pinion Wheel in response to displacement of saidtoothed rack; and actuating means coupled to said body and to saidtoothed rack for displacing said rack relative to said body.

2. A compression tool in accordance with claim 1 wherein said e'ccentriclinkage coupling said pinion wheel to said movable die comprises:

a pivot journal mounted to said pinion wheel and having a central axiswhich is eccentric with respect to the central axis of said pinionwheel;

a thrust bolt movably coupled to said body for relative motion in linewith said movable die; and a pressure transfer member coupled to saidthrust bolt and to said pivot journal.

3. A comparison tool in accordance with claim 1 wherein said actuatingmeans comprises a movable handle which is pivotally coupled to said bodyat a first pivot axis and is pivotally coupled to said toothed rack at asecond pivot axis which is eccentric with respect to said first pivotaxis.

4. A compression tool in accordance with claim 1 wherein said actuatingmeans comprises a fluid-pressure actuated piston assembly having apiston and cylinder which are displaceable relative to one another andare coupled between said body and said toothed rack for displacing saidrack relative to said body.

5. A compression tool in accordance with claim 4 wherein saidfluid-pressure actuated piston assembly is mounted as a movable handlewhich is pivotally coupled to said body at a first pivot axis, and ispivotally coupled to said toothed rack at a second pivot axis beingeccentric with respect to said first pivot axis; said further comprisingreleasable locking means coating with said piston assembly to preventpivotal motion of said piston assembly as a movable handle.

6. A compression tool in accordance with claim 4 wherein said eccentriclinkage coupling said pinion wheel to said movable die comprises: apivot journal mounted to said pinion wheel and having a central axiswhich is eccentric with respect to the central axis of said pinionwheel; a thrust bolt movably coupled to said body for relative motion inline with said movable die; and a pressure transfer member coupled tosaid thrust bolt and to said pivot journal.

7. A compression tool in accordance with claim 6 wherein said toolfurther comprises releaseable detent means for limiting motion of saidpinion Wheel to rotation in one direction only.

References Cited UNITED STATES PATENTS 2,705,432 4/1955 Lazar 724092,861,490 11/1958 Rozrnos 72449 3,342,059 9/1967 Laux 72410 2,494,963 1/1950 Ray 72409 X 2,587,096 2/1952 Berger 72410 X 2,688,231 9/1954Northcutt 72409 X 2,696,850 12/1954 Peterson 72409 2,931,260 4/ 1960Townshend 72409 FOREIGN PATENTS 737,152 9/ 1955 Great Britain.

891,454 3/ 1962 Great Britain. 1,341,705 9/1962 France.

CHARLES W. LANHAM, Primary Examiner E. SUTTON, Assistant Examiner US.Cl. X.R. 72453

